Stress-homogenized spatial architectures via entropy-driven self-assembly enabling high-performance and durable lithium extraction.

Abstract

The global transition to sustainable energy demands efficient lithium extraction from brines. While electrochemical lithium extraction using LiMn₂O₄ (LMO) holds great promise, its practical application is hindered by mechanical degradation caused by anisotropic volume changes and stress accumulation during cycling. Herein, we present an entropy-driven amphiphilic self-assembly strategy that engineers stress-homogenized multilayer core-shell architectures, which innovatively mitigates stress accumulation by tuning the internal geometric structure to optimize stress-strain behavior, thereby synergistically enhancing ion distribution, transport kinetics, and electrochemical stability. This hierarchical interlayer architecture ensures uniform Li⁺ distribution and redistributes internal stresses, mitigating localized stress concentrations and lattice expansion to preserve structural integrity throughout cycling. The optimized LMO establishes a dual benchmark for both capacity and cycling stability in hybrid capacitive deionization, achieving a remarkable lithium extraction capacity of 4.78 mmol g^-1 with 96% retention over 100 cycles, outperforming both its unoptimized counterpart and other reported materials of the same type. Finite element simulations further elucidate a 48% reduction in maximum stress compared to disordered counterparts, underscoring the critical coupling between ion diffusion and stress evolution. This paradigm provides a pathway for developing advanced materials with intrinsically stable architectures for sustainable lithium extraction.